Spacing Effects in Real-World Classroom Vocabulary Learning
Sobel, H. S., Cepeda, N. J., & Kapler, I. V. · 2011
grade Crctindependentreplicatednumbers spot-checked
Sample
39 fifth-graders (within-subjects)
Population
Fifth-graders (~10 yr), real classroom, teacher-delivered, authentic GRE vocabulary.
Design
Rare authentic-content classroom spacing RCT. Each child did both a massed (0-day) and a 1-week-spaced condition; definition recall 5 weeks later.
Key findings
Spacing generalizes to real classrooms: a 1-week gap roughly tripled 5-week vocabulary retention vs massing (20.8% vs 7.5%), advantage larger at delay. Limits: N=39, proximal aligned recall.
Genetic confound
Low: within-subject design controls ability fully.
Replication notes
Extends the lab spacing effect to K-12 classroom vocabulary; small N.
DOI / URL
10.1002/acp.1747
Effects
| Outcome | Metric | Value | Measure | Timing | Vs | Horizon | Class |
|---|---|---|---|---|---|---|---|
| 7-day spaced vs massed, 5-week delayed recall | % correct | spaced 20.8% vs massed 7.5% (~2.8x) | researcher-designed | delayed 5wk; classroom | active-alternative | under-1yr | domain-skill |
| Spaced vs massed, immediate | % correct | ~12.2% vs 8% (advantage larger at delay) | researcher-designed | immediate; classroom | active-alternative | end-of-treatment | domain-skill |
Cited by
- Spaced (distributed) practicestrong supportconf: highgc: low